인공 와우 이식술에서 내이 기형과 내이도 협착의 임상적 의의

Abstract

To assess the audiologic and surgical outcomes for cochlear implant patient with inner ear malformation, We retrospectively reviewed of 110 cochlea im-plant cases from 2002 to 2005. Eighteen patients with known inner ear mal-formations determined on computed tomography (CT) or temporal magnetic reson-ance image. Patients were grouped based on cochleovestibular anomaly as follows： hypoplastic cochlea (n=1), incomplete partition (n=6), isolate enlarged vestibular aqueduct (n=4), semicircular canal anomaly (n=2) and narrow internal auditory canal (IAC) (n=5) were identified. Cerebrospinal fluid (CSF) leaks through the cochleostomy were encountered in 3 of 18 patients. The specific type of inner ear malformation determined by CT fa-iled to predict an intraoperative CSF leakage. All CSF leaks were controlled intrao-peratively with temporalis muscle plugs or fascia. Facial nerve anomaly was identified in 2 of 18 patients and was associated with narrow IAC and lateral semicircular canal agenesis. There were no postoperative facial nerve palsy, meningitis and revision surgery. In terms of audiologic performance, patient with inner ear malformations may perform very well except patients with narrowing of the internal auditory canal. We performed cochlear implant in patients with narrowed IAC who have residual hearing approved by ASSR (n=4) or parent’s report (n=1). But, three of them failed to response with a sensation of sound. Two of them only hear the loud environmental sound.